Proposed Changes to PTCS Duct Sealing Specifications & Standards RTF January 23 rd 2033 Bob Davis & Bruce Manclark

Current Specifications Systems must be sealed with mastic –Mastic comes out of a bucket - not off of a roll –UL 181 tape may be used to provide service access Worst case depressurization test must be below minus 3 Pascals Must have UL listed Carbon Monoxide alarm if combustion appliances are present Testing must be performed by a Climate Crafter certified technician Room by room heat loss required for duct sizing in accordance with industry standards No recommended changes

Current Tightness Standards New Construction –Total leakage or 50PA to exterior cannot exceed: 6% of floor area (2,000 sq. ft. house max leakage of 120 CFM) OR 75 CFM No recommended changes

Current Tightness Standards Existing Homes –Achieve a 50% reduction in exterior by duct sealing –Leakage to exterior less than 10% of conditioned floor area (2,000 sq. ft. house max leakage of 200 CFM) –All pressure pans less than 1 Pascals –Proposed changes: Eliminate the use of Pressure Pans as a standard

Why Eliminate Pressure Pans Not a solid standard –Many variables other than holes to the exterior affect their readings Filter Inside coils Sq. inches of registers Other inside leakage Tightness of seal (carpet vs. bare floor)

Why Eliminate Pressure Pans Crews receive inconsistent feedback –Small reductions in holes may mean large pressure pan reductions –Large reductions in holes may mean small pressure pan reductions Impossible to make energy savings projections from pressure pan numbers

Side by Side Comparisons of Pressure Pans and Duct Blasters 141 unsealed duct systems in western Oregon –All crawl space homes –Only shows average pressure pan numbers

Mobile Home Data 41 mobile homes in Eugene, Oregon –Good variety of double wides and single wides –Good variety of ages –Pre and post results on same homes